staging: octeon-usb: delete cvmx_usbnx_clk_ctl_cn50xx

Add the missing bits to common clk ctl definition, and we can delete
duplicated definitions.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>